+ return scm_make_real (0.0);
+}
+
+MAKE_SCHEME_CALLBACK (Rest_collision, force_shift_callback_rest, 2);
+SCM
+Rest_collision::force_shift_callback_rest (SCM rest, SCM axis)
+{
+ Grob *rest_grob = unsmob_grob (rest);
+ assert ((Axis) scm_to_int (axis) == Y_AXIS);
+
+ Grob *parent = rest_grob->get_parent (X_AXIS);
+ if (Note_column::has_interface (parent))
+ return force_shift_callback (parent->self_scm (), axis);
+ else
+ return scm_make_real (0.0);